Would be very surprised if there is a CIO/CTO without a public/private/hybrid cloud adoption roadmap to show...well maybe if your main business is operating legacy data-centers. Even the later gang is wondering how to turn the decade long infrastructure investment into a cash cow. But need to be careful, cloud does not mean AWS or lockins into popular public cloud. You are right API driven architectures are the way to go in any combination cloud you build. Be it provisioning, scheduling, orchestration, scaleout...APIs are the new delivery bus.
We're talking to many new gen cloud companies that are already in production and have a burgeoning business that they have to support. They're all "sensitive" to cloud lock in and portability is definitely of concerns. What's also interesting is that many have moved from cloud to cloud like AWS to Azure. And many have a combination of clouds as well - a lot more than an I had anticipated!